Microsatellite DNA profile of genealogical families in the East Bulgarian horse breed
Iliyana Sabeva
Abstract: The aim of the present study was to make a DNA profile of the genealogical families of the East Bulgarian Horse breed and to determine the genetic distances between them. The results of the genetic mapping of 266 horses with respect to 15 microsatellite markers (SSRs – simple repeat sequences from two to six nucleotides) were analyzed as follows: AHT4, AHT5, ASB2, ASB17, ASB23, HMS1,
HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10 and VHL20. High polymorphism was found in the loci ASB17, ASB23 and ASB2. Genetic diversity in HTG10 and VHL20 was moderately high. Observed, expected and average heterozygosity are close to those of the breed. The specific profile of each of the studied families was determined by the alleles with low frequency and by the proportion of homozygous genotypes at the loci HTG4, AHT4, HTG7, HMS1 and HTG6, where heterozygote deficiency was observed. Rare combinations in riding horses are G in AHT4 in the Ohota family; T in ASB23 at Likuyushta and Leila; S, T and U in ASB23 at Longuza, and S and U in ASB23 at Kilia. Q in HMS3 occurs in horses of the Likuyushta and Ohota families, and Q in VHL20 and T in HMS3 only in horses of the Leila family. The R allele was found in the HMS2 locus in the families of Likuyushta and Nerazdelna and in HMS6 in Nerazdelna and Ohota. Close genetic links have been established between the families of Likuyushta and Leila, and
between Longuza and Ohota. Over the past two generations, there has been a reduction in genetic distances between the families of Longuza and Ohota, and between Nerazdelna, Likuyushta and Leila.
HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10 and VHL20. High polymorphism was found in the loci ASB17, ASB23 and ASB2. Genetic diversity in HTG10 and VHL20 was moderately high. Observed, expected and average heterozygosity are close to those of the breed. The specific profile of each of the studied families was determined by the alleles with low frequency and by the proportion of homozygous genotypes at the loci HTG4, AHT4, HTG7, HMS1 and HTG6, where heterozygote deficiency was observed. Rare combinations in riding horses are G in AHT4 in the Ohota family; T in ASB23 at Likuyushta and Leila; S, T and U in ASB23 at Longuza, and S and U in ASB23 at Kilia. Q in HMS3 occurs in horses of the Likuyushta and Ohota families, and Q in VHL20 and T in HMS3 only in horses of the Leila family. The R allele was found in the HMS2 locus in the families of Likuyushta and Nerazdelna and in HMS6 in Nerazdelna and Ohota. Close genetic links have been established between the families of Likuyushta and Leila, and
between Longuza and Ohota. Over the past two generations, there has been a reduction in genetic distances between the families of Longuza and Ohota, and between Nerazdelna, Likuyushta and Leila.
Keywords: East Bulgarian Horse breed; genetic diversity; inter-families differentiation; microsatellite markers
Date published: 2023-04-28
Download full text